United States. Department of the Treasury. "Subscription figures for current exchange offering, February 17, 1970," in United States. Department of the Treasury. "Volume 168," Press Releases of the United States Department of the Treasury (February 2, 1970 - April 30, 1970) : 62-64. https://fraser.stlouisfed.org/title/6111/item/587011/toc/541671 , accessed on June 25, 2024.